1. Field of the Invention
This present invention refers to a net made from a multi-layer film, the net being made from knitted yarn which has been thermally treated and compressed.
Further the invention pertains to manufacturing and production method pertaining to knitted products made from synthetic yarns having controlled properties.
2. Description of the Prior Art
As already known, in order to manufacture various nets, prestretched or non-prestretched synthetic yarns are widely used, which, depending on the pattern and knitting schema, yield a variety of different products. Such products are pipe-shaped nets used for fruit packaging, straw nets used for pallet wrapping-shading, nets used for protection against hailstorms, insects, sunlight, low temperatures, etc. (FIGS. 1 and 2). Such nets are manufactured by a knitting machine that may be a Raschel knitting machine.
All such products have certain features in common. The fibers which they are knitted from are made of homogenous materials or of a combination of various mixed materials. When mixing different materials, a sufficient level of control over the properties of the manufactured product could not be achieved. As for the effective use of such materials, their mechanical properties—like elasticity, tensile strength and hardness—are quite important. Equally pursued is the reaction of single-layer yarns with regard to permeability, strength and also solar radiation filtering.
Another common characteristic of such net products is that, if they are severed or torn and not properly repaired or processed at the damaged area, the said nets tend to lose their strength and not only are they destroyed, but are also torn to pieces, and their remainders are scattered about or cause entanglements.
In addition, a number of single-layer knitted products, such as pallet wrapping straw, have a certain drawback as they tend to produce fine threads when cut. These fine threads create serious problems, since they block rolling conveyors, interfere with photocells, etc.